Speed control for lifting jacks



July 14, 1925.

F. GORMLEY SPEED CONTROL FOR LIFTING JACKS Filed April 4. 192's 2Sheets-Sheet 1 Inventor: .FrankL. Gormlc y,

July 14, 1925.

F. L. .GORMLEY SPEED CONTROL FOR LIFTING JACKS 2 Sheets-Sheet 2 FiledApril 4;; 1925 Inventor; I'ranhL Gormley,

Patented July 14, 1925.

UNITED STATES FRANK L. GORMLEY,;OF BROOKLINE, MASSACHUSETTS.

SPEED ('JON'IFROILFOB LIFTING JACKS.

Application filed April l, 1925. Serial No. 20,643.

To all whom it may concern:

Be it known that I, FRANK L. GoRMLnY, a citizen of-the'United States ofAmerica,

and a resident of Brookline, county of Norfolk, State oflVIassachusetts, have invented certain new and useful Improvements inSpeed Controls for Lifting Jacks, of which the following is aspecification.

This invention relates to lifting jacks adapted to lower at high speedand has for its object the provision of means whereby the load may beretained in raised position under normal conditions by a rotatable worm,and its lowering readily controlled by the operator oscillating a leverand rotating said worm.

These objects are attained by the mechanism illustrated in theaccompanying drawmgs.

For the purpose of illustrating the invention, one preferred formthereof is illus trated in the drawings, this form having been found togive satisfactory and reliable results, although it is to beunderstood-that the various instrumentalities of which the inventionconsists can be variously arranged and organized, and the invention isnot limited to the precisearrangement and organization of theseinstrumentalities as herein shown and described except as required bythe scope of the appended claims.

Of the drawings;

Figure 1 represents a vertical section of a liftingjack embodying theprinciples of the present invention, and

Figure 2 represents a section of the same on line 2, 2 on Fig. 1. 7

Similar characters indicate like parts throughout the several figures ofthe drawings.

In the drawings, 10 is a base having threaded thereto a housing 11, theupper end of whichis provided with a bearing 12' for i p i alsoformed'upon the cover plate 34: so that the ram or movable member 13.

The lower end of said ram 13 has secured therein a nut 14 to which isthreaded the lifting screw 15 having keyed toits lower end a bevel gear16 meshing with a bevel pinion 17 on an actuating shaft 18, on the outerend of which is mounted an actuating lever 19 of any well knownconstruction.

The base 10 is provided with an upwardly extending annular flange 20positionedon the top of the baselO, a plate 21 having an annular groove22 in its upper face in which are disposed a plurality of anti-frictionmembers, such as the balls 23. I

Superimposed upon these balls 23 is another plate 241- on the top ofwhich rests the bevel gear 16..

By actuating the lever 19 the pinion 17 may be rotated and this rotarymovement is transmitted to'the lifting screw 15 through the gear 16,thereby causing the ram 15 to be raised withinthe housing 11.

Keyed to theactuating shaft 18 are two ratchets 25 spaced apart andbetween these ratchets is mounted a worm gear 26 which is adapted to berotated only during the lowering of the load.

On the opposite-sides of this gear 26 are two sets of spring pressedpawls 27 one set of which engage the teeth of one ratchet 25 at pointsintermediate the pointsof engagement of the other set of pawls 27 withits coacting ratchet 25.

In lifting the load the actuating shaft is rotated in the direction ofthe arrow at on Fig. 2, and when so actuated the rotating ratchets 25will not engage'the pawls 27 and no movement will be imparted to theworm gear 26. i

This worm gear 26 meshes with the worm 28, the ends of which are mountedin bearings 29 in the housing 11, and the pitch of the thread of whichpreferably is such that it will not be rotated under the weight of theload.

To one end of the worm is secured a bevel pinion 30, the teeth of whichmesh with a bevel gear 31 having a cylindrical stem 32 revoluble in abearing 33 in a cover plate 34 secured in any well known manner to thehousing 11.

'.of said gear 31. y

The bearing for the actuating shaft 18 is when said cover plate isremovedall working elements are removed therewith except the liftingscrew 15, its gear 16 and supports therefor, the worm 28, and the ram13. The cover plate 34 also has an extension 36, to which, at 37, ispivoted a lever 38 to which at 39 is pivoted one end of a link 40, theopposite end of which is pivoted to the gear- 31 atffl. I The upper endof the lever 38 has formed thereon or secured thereto a cylindrical thesegment 46 formed upon or secured to the extension 36,thereby lockingthe lever 38 in adjusted position.

lVithin the tubular member 43 is thread-' ed an annular nut 47 throughwhich extends a cylindrical handle 48 having a ball shaped knob 49 atits upper end and an annular flange or head 50 at its; lower end.

Between the nut 47. and the upper end of cylindrical member 42 is. a,spring 51 whichis adapted to force the tubular member 43' downwardlyinto engagement with the segment 46. i

WVhen it is desired to operate the handle 48 the operator seizes theknob 49 and moves it upwardly untilthe head 50 contacts with thenut 47,and then continues the upward movement until the spring 5,1 is;compressed suiiiciently to permit the disengagement oi? the projection44 from the teeth 45.

The operator may then. oscillate the lever 38 and through the link 40:impart rotary movement to thegear 3-1,thr0ngh the pinion 30, worm- 28,and worm gear 26.-

As previously stated the thread of the worm 28 has apitch which willprevent its rotation by the rotation o-it the? Worm geait 26, and as aconsequence-the loadupon the ram 13 will be sustained in itsraiSed posistionuntil the, worm 28 is positively rotated by oscillating the handle48. 1 r

The weight of the; load upon the ram 13 has a tendency to move theratchet-s, 25 in the direction of the arrow b'on Fig. 2, but

as the gear 26 is prevented from rotatingby its engagement with theworm. 28 and;

the pawls 27v are engaged with the-.WOrm128 it is obvious that the; rantwill be prevented from moving downwardly.

When, it is. desired; to lower the; load; the

operator oscillates. the; handle 48,; rotatingthe; Worm 28: and' ormgear-26, and: as the. pawls27. on the la-ttermove in the; directionofthe arrow 2),, the weight of the'load on the ram 13 will cause theratchet -25, to to llow said: pawls. and remain in engagement therewith.

As long as the handle 48 is oscillated; the

loadwill continue to lower, but when said load has been loweredsuificiently thev op erator ceases to OSGillate-the handle-and theprojection 44- will, immediately engage, the

and retained in its raised position until by manually operated mechanismthe lowering ofthe ram. under its load is permitted.

The jack does not lower automatically and is not lowered by means of acrank but such lowering is wholly effected by the oscillation, of thecontrolling lever;

The speed of lowering may be regulated by the operator actuating thecontrolling lever 38 faster or slower as the case may be.

Normally the jack is locked bythe engagement of the projection 44 withthe teeth 45. and th load. cannot be lowered until this projection isdisengaged from said teeth.

If desired the cover plate 34 may be dis pensed with and a wall formedon the housing '11 to support the; actuating shaft 1 8 and the elementscoasting therewith.

' It is obvious that whether or not the jack lowers. automatically itslowering may be- I trolling lever.

Other forms of gearing may be. substituted. for the bevel gears shewnwithout atfecting. the principles of the present in vention.

The worm gear could be secured directly to, the shaft .18 and rotateduring both the operation of lifting and lowering.

It isbelievedtha-t the operation and many advantages of the invention:will; be understood without further description.

Having thus vd S ribedmy invention I; claim-z 1-. In a lifting jack, thecombination, of an actuating shaft, adapted to be rotated in onedirection to raise the load supporting member; two ratchets securedthereto; a gear interposed between said ratchets and loosely mounted onsaid shaft; pawls on the opposite sides. of," said gear adapted to ens.gage said ratchets during the rotation of the-shaft intheoppositedirection the pawls on oneside engaging the teeth ofone'ratchet at points intermediate the. engagement of theether of? pa-Wls;with; the other ratchet; andmeans for controlling the rotationotsaidigear: during the loweringoli the load supporting member,

2. In a lifting jack, the combination of an I actuating shatt adaptedtorbe rotated. in one direction to raisethe load supportingmember; tworatchets secured thereto; a. worm gear interposed between said: ratchetsand l sely mounted onisaidshaft; pawls on the opposite; sides of! said"gear adapted toengage said ratehets dnringthe rotation of the shaft inthe, opposite; direction, the pawls on one side: engaging the-teeth ofone ratchet atpoints intermediate the" engagement of theotherset of;pawls with the other ratchet; a worm meshing with the teeth of said igear; and means for; controlling the rotation of: said worm; during thelowering of the load supporting member. s

3. In a lifting jack, the combination of an actuating shaft adapted tobe rotated in one direction to raise the load supporting member; aratchet secured. thereto; a worm gear loosely mounted .on said shaft andcarrying pawls adapted to engage said ratchet during the lowering ofsaid load supporting member; a worm in mesh with said worm gear; andmechanism for regulating the rotation of said worm including a manuallycontrolled oscillating lever linked to a member rotatable with saidworm.

4. In a lifting jack, the combination of an actuating shaft adapted tobe rotated in one direction to raise the loat supporting member; aratchet secured thereto; a worm gear loosely mounted on said shaft andcarrying pawls adapted to engage said ratchet during the lowering ofsaid lead supporting membe'; a worm in mesh with said worm gear; a.bevel pinion rotatable with said worm; a bevel gearin mesh therewith; apin eccentric ally disposed on said bevel gear; a pivoted lever; and alink between said pin and lever.

5. I11 a lifting jack, thecombination of an actuating shaft adapted tobe rotated in one directionto raise the load supporting member; aratchet secured thereto; a worm gear loosely mounted on said shaft andcarrying pawls adapted to engage said ratchet during the lowering ofsaid load supporting member; a worm in mesh with said worm gear; a bevelpinion rotatable with said worm; a bevel gear in mesh therewith; a pineccentrically disposed on said bevel gear; a pivoted lever; means forlooking said lever in fixed position; and a link between said pin andlever.

6. In a lifting jack, the combination of an actuating shaft adapted tobe rotated in one direction to raise the load supporting member; a.ratchet secured thereto; a worm gear loosely mounted on said shaft andcarrying pawls adapted to engage said ratchet during the lowering ofsaid load supporting member; a worm in mesh with said worm gear; a bevelpinion rotatable with said worm; a bevel gear in mesh there'- with; apin eccentrically disposed on said bevel gear; a pivoted lever;automatic means for locking said lever in fixed position; and a linkbetween said pin and lever.

7. In a lifting jack, the combination of an actuating shaft adapted tobe rotated in one direction to raise the load supporting member; aratchet secured thereto; a worm gear loosely mounted on said shaft andcarrying pawls adapted to engage said ratchet during the lowering ofsaid load supporting member; a worm in mesh with said worm gear; a bevelpinion rotatable with said worm; a bevel gear in mesh therewith; a pineccentrically disposed on said bevel ear; a pivoted lever; a fixedtoothed sector; a spring actuated member on said lever adapted tocoact'with said sector; and a link between said pin and lever.

8. In a lifting jack, the combination of an actuating shaft adapted tobe rotated in one direction to raise the load supporting member; aratchet secured thereto; a worm gear loosely mounted on said shaft andcarrying pawls adapted to engage said ratchet during the lowering ofsaid load supporting member; a worm in mesh with said worm gear; a bevelpinion rotatable with said worm; a bevel gear in mesh there with; a pineccentrically disposed on said bevel gear; a pivoted lever; a fixedsector having depressions therein; a. cylindrical member provided witha. projection to engage the depression of said sector and having anannular flange on its inner wall and spaced from the bottom of saidmember; a casing on said lever in which said member is movable endwise;a handle extending through the top of said casing and having a shoulderon the lower end thereof adapted to engage said flange; a. springbetween said flange and the'top of said casing.

9. In a. lifting jack, the combination of an actuating shaft adapted tobe rotated in one direction to raise the load supporting member; aratchet-secured thereto; a worm gear loosely mounted on said shaft andcarrying pawls adapted to engage said ratchet during the lowering ofsaid load supporting member; a. worm in mesh with saidworm gear; a bevelpinion rotatable with said worm; a bevel gear in mesh therei with; a pineccentrically disposed on said bevel gear; a pivoted'lever; a fixedtoothed sector; a cylindrical member provided with a projection toengage said sector and having an annular nut threaded to its inner walland spaced from the bottom of said member; a casing on said lever inwhich said member is movable endwise; a handle extending through thetopof said casing and having a shoulder on the lower end thereof adapted toengage said nut; and a spring between said nut and the top of saidcasing.

10. In a lifting jack, the combination of an actuating shaft adapted tobe rotated in one direction to raise the load supporting member; aratchet secured thereto; a worm gear loosely mounted on said shaft andcarrying pawls adapted to engage; said ratchet during the lowering ofsaid load supporting member; a worm in mesh with, said worm gear; amember rotatable with said worm; and a manually controlled oscillatinglever linked to said rotatable member and adaptedto regulate therotation of said worm.

11. In a lifting jack, the combination of gear loosely mounted on saidshaft and carrying pawls adapted. to engage said ratchet during thelowering of said load supporting member; a worm in mesh with saidwormgear and the thread of which has a pitch sufiieient to retain theload. in raised position; a member rotatable with saidworm and mechanismfor regulating the rotation of. said worm including a man.-ually-controlled oscillating lever linked to said rotatable member.

12. In a lifting jack the combination of an. actuating shaft adapted tobe rotated in one direction to raise the load-supporting member; aratchet secured thereto; a worm gear loosely mounted on said shaft andcarrying pawls adapted to engage said ratchet during the lowering ofsaid load supporting member; a worm in mesh with said worm gear; abevelpinion rotatable with said worm; a bevel gear in mesh there with;and manually controlled mechanism forrotating said bevel gear.

13. In a lifting jack the combination of an actuating shaft adapted tobe rotated in one directionto raise the load supporting member; aratchet secured thereto; a worm gear loosely mountedv on said shaft andcarrying pawls adapted" to engage said ratchet during the lowering ofsaid. load supporting member; a worm in mesh with said. worm gear; a.bevel pinion rotatable with said worm; a. bevel gear in mesh therewith;a pin eccentrically disposed on said bevel gear; a lever adapted to beoscillated and thereby rotate said bevel gear; means for locking saidlever in fixed position; and

a link between said pin and lever.

1.4;. In a lifting jack, the combination of an actuating shaft adaptedto be rotated in one direction to raise the load sup-porting member; aratchet secured thereto; a worm gear loosely mounterit on said shaft andcarrying pawls adapted to engage said ratchet during the lowering ofsaid load sup-porting member ;i a worm in mesh with said worm gear and peventing its rotation under normal conditions; -a bevel pinion rotatablewith said Worm; a bevel gear in mesh there-with; and.- oscil-latingmeans for rotating said bevel gear thereby rotating said worm 'andpermitting. the rotation of said worm gear under the weight of the said.worm gear; a bevel.- pinion rotatable with said'wor1n.;:a bevelgear invmesh there with; and means for positivelyrotatingsaid bevel gear andworm thereby permitting the rotation of said worm gearunder the weightof the load.

1.6. In a lifting. jack the combination of a load supporting member ;1means for raising. said member; and independent mechanism coacting withsaid actuating shaft for controlling; the lowering of the load supporting member and including manually actuated oscillating lever linkedto a member rotatable with. said: wornr.

Signed by meat: 74.6 Old South Bldg, Boston, Mass, this 13th day ofMarch,.1925.

' FRANKL. GORMLEY. \Vitnesses \VALTER LQMBARD; NATHAN C. LOMBARD.

